Phonograph-reproducer.



H; T. SCOTT.

PHONOGRAPH REPBODUGBR.

APPLIOATIOH FILED 11017.21, 1911.

Patented Oct. 1, 1912.

2 SHEETS-SHEET 1.

. T. SCOTT.

PHONOGRAPH REPRQDUGER.

' APPLIOATION FILED Nov.z1,1s11..

B SHEETS-SHEET 2.

lili

HARRY SCOTT, OF LOSANGELES, CALIFORNIA.

PHONOGRAPH-REPRODUCER.

Specification of Letters Patent.

Patented Oct. 1, 1912.

Application led November 21, 1911. Serial 661,485.

To all whom ttmay concern: y.

Be it known that I, HARRY T. Scoji'r, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles, State of California, have invented new and useful Improvements in Phonograph-Reproducers, of which the following is a specification.

This invention relates to acoustic devices in general and to a phonograph reproducer in particular; and it has to do with certain improvements which renderithe reproducer more simple in construction and capable of giving better, cleaner and finer results than has heretofore been possible.

The prime object of my present invention is the elimination of all looseness of the working parts of a reproducer, together with the provision of a mechanism of such character that the reproducing point is ald lowed free movement in every direction. Following this primary object, my inven tion (as applied to the form of reproducer in which the stylus or reproducing point is mounted on a stylus plate and the stylus plate is in turn mounted on the sound box or other stationary frame) r,consists in a novel mountingfor the stylus plate upon the sound-box or stationary frame and in a` novel mounting of the stylus upon ythe stylus plate. Broadly considered, the stylus may be mounted upon the stylus plate in any desired manner; my broader conception of invention including only my novel method of mounting the stylus plate, or other equivalent member which carries the stylus mounted thereon in any desired manner, upon the stationary box or frame. And this method of mounting the stylus plate. fundamentally comprises what Iterm a single point suspension, the stylus plate only having a single point of engagement with the stationary supporting member and being more or less perfectly balanced on that point of engagement. In order to rotate the stylus plate about its' vertical 'aa'.isdeter-` mined by this point of engagement, I employ a torsion spring whic '1s attached to the stylus plate directly beneath the point of support and which acts, about the vertical axis therethrough; and this same torsion spring also acts as a tension spring, if desired, to pull the stylus plate down into position so that it will not leave itsv point of support. The amount of tension depends entirely upon the weight of the stylus plate itself. If the stylus plate is constructed rather heavily, its own weight is sufficientto hold it in place; if it is constructed more lightly,` then the t-ension spring will be utilized.

The above out-lined single point suspension of the stylus platewill be seen to eliminate all looseness and at. the same time allow the stylus plate free movement in every di rection. My method of mounting the stylus o-n the stylus plate also eliminates all looseness at that point. Preferably the stylus is provided with a vertical axis which rests in semi-cylindrical depressions in the stylus plate, and a small spring is utilized topress the axis into the depressions and hold 1t accurately in position.

There are other features of construction and combination which I wish to emphasize along with those above outlined, and which are more fully explained in the following specification and illustrated in the accompanying drawings, in which:

Figure 1 is a plan view of my improved device. Fig. 2 is a front elevation of the same. Fig. 3 is a side elevation of the same. Fig. 4 is an enlarged horizontal section taken on line 4 4 of Fig. 2. Fig. 5 is an enlarged vertical section taken on line 5 5 of Fig; 2. Fig. 6 is an enlarged' section taken on line 6 6 of Fig. 2. Fig. 7 is a vertical section taken on line 7 7 of Fig. 4. Fig. 8 is a section taken on line &8 of Fig. 7. Fig. 9 .is an enlargement of the portion of Fig. 2 showing the mounting of the stylus on the stylus plate. Fig. 10 is an enlarged cross section of the sound box of my improved device. Fig. 11 is a perspective view of a retaining ring for holding the vibrating diaphragm in the sound box. Fig. 12 is a section taken online 12 12 of Fig. 6. Fig. 13 is a view similar to Fig.

1, showing a modied form of stylus plate mounting. Fig. 14- .is a front elevation' of the same.A Fig. 15 is anenlarged, detall section taken on line-15'-"15 of Fig. 14. Fig. A

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and serves to clamp it tightly about the upright 5. Upright 5 carries on its upper end a plate 10 to which a sound box 12 is secured, `the box 12 being of ordinary constr uction except that I may vary the proportions to suit my own peculiarv mecl anism. W'ithin this sound box 12 there is contained a diaphragm 13 of any desired material and formation, and the circular edge of t-he diaphragm is held between two rings 14- and 15 having inclined surfaces adjacent to each other and engaging with the peripheral portions of the diaphragm. Ring 14 is preferably solid while ring 15 is preferably divided at 1G, as is best shown in Fig. 11; so that t-he ring 15 may be forced down on the diaphragm and force the diaphragm into the configuration shown, the ring 15 expanding slightly while being forced down along the inclined face of the two rings and pulling the edge of the diaphragm out with it, thus imparting to the diaphragm a tension in a radial direction. The ring 15 is held in placeby means of a. screw threaded ring 17 il which is screwed into the sound box in the ordinary manner. The sound box itself is held on plate 10 by screws 18 or by any other suitable holding means. The diaphragm 13 has a connecting wire 19 which serves to connect with the stylus lever 20;

I have shown a stylus plate 30 which has the usual circular portion 31 immediately before the sound box 12 and which has an extension 32 carrying an adjustable counterbalance 33 on its end. At al point where the extension 32 joins the circular portion 31 there is provided an opening 35. A supporting pin 36 is mounted in a vert-ical pesition in the stylus plate and has a pointed end which, when counter-balance 33 is properly adjusted, is as closely as possible coincident with the center of gravity of the.

wholeA stylus plate. In order to insure good results from the reproducer, this condition must be approximately fulfilled; although variation of this point from the center of gravity along a vertical line therethrough does not impair the working quality as much as does displacement along a horizontal line through the center of gravity. The point of pin 36 restsin a shallow pointed depression 37 in a member 38 which is solidly mounted in a. portion of box 12; but this member 38 may be mounted in any other stationary part of the mechanism. Immediately below the point of suspension of the stylus plate there is secured a pin 40 around which a torsion and tension spring 41 is soldered or otherwise secured. This spring 41 typifies, in theprefe'rred form of device, any tension and torsion means and extends vertically downwardly directly beneath the point of suspension of the stylus plate and is secured at. its lower end to a vertical pin 42. This pin 42 passes through the end of an arm 43 and the pin is provided with an enlarged portion 44 of polygonal cross section which engages in an aperture 45 of similar section so that the pin 42 is prevented from turning. A small thumb nut, 4G proides means for pulling pin 42 downwardly so that it may be rotated to put any desired torsion on the spring 41.

Spring 41 tends to move the stylus plate in the direction indicated by the arrow in Fig. 1; and the plate is prevented from moving excessively in that direction by means of a link which* passes around a pin 51 in the end of the stylus plate. This link 50 passes through the box 12 and is moved longitudinally from its rear end through the medium of an arm 52 mounted on the upper end of a vertical rod 53. This rod 53 is operated to move the stylus plate into and out of operative position; but the mechanism to effect this movement need not be entered into in this specification. Stylus 20 is pivotally mounted on a vertical axis which is mounted on the stylus plate and held in engagement therewith in a novel manner The stylus 2O moves about its pivot in a horizontal direction, and the stylus point 20a engages with a cylindrical record G1 which has its axis in a vertical position. Axis 60 of the stylus rests in two small approximately semi-cylindrical vertical grooves in the stylus plate, these grooves being designated by the numeral 65. It is desired that these grooves be not of great length, as it is more easily possible to make the axis 60 fit accurately when the grooves are short. But it is desirable to make the axis 60 somewhat longer than the grooves would provide for; and so the grooves are limited on their outer ends by apertures 66 which may pass completely through the stylus plate. The grooves are limited on their inner ends by t-he slot G7 in which the stylus 20 is placed7 this slot 67 conneeting with an enlarged aperture GS in which the end of stylus 20 is located and through which the connection 19 passes. The axis 60 is held in place in the semi-cylindrical grooves by means of a small double cnded spring 70 secured by a screw 71 to the stylus plate. The ends of this spring press in notches 70 on the axis 60 and press it into the grooves; the engagement of the spring with the notches preventing endwise ,movement of the axis 60. The axis tits into the grooves accurately so that there is no looscness whatever. The stylus 2O is suiiicientl'y loose in slot 6,7 to prevent-it engaging with the edges of the slot.

With the stylus plate hanging in a vertical plane, as illust-rated, and swinging horizontally into and out of engagement with the record, it will be seen that no part ot' the weight of the styliis plate comeson the record at all. The only force tending to engage the stylus plate or the stylus with the record is the torsional torce of the spring 41; and this may be adjusted as is desired. In the form of reproducer in which the weight of the stylus plate is supported by the stylus resting upon the record, the weight of the stylus plate is limited very closely. On the weight and inertia of the stylus plate depends the elieiency of transmission of the sound vibrations from the stylus point to the vibrating diaphragm in the sound box. In my construction I may increase the weight of the stylus plate, and therefore its inertia as to movement about its single point of support, very greatly; and I am consequently enabled to decrease the vibrational movement of the stylus plate, to render the stylus plate more nearly stationary while still movable to follow any variations in the surface of the record due to eccentricity, and thus keep the vibrations more completely concentrated in the stylus andthe connecting mechanism to the vibrat-ing diaphragm. This is a feature of prime importance; and my method of single point suspension and of holding the stylus plate in place by the torsion vand tension spring enables me to employ the methods and mechanisms just described.

In the foregoing described mechanism it will be seen that I have completely avoided all difficulties of the stylus point following any radial variation in the record, allowing the stylus point to move to.,and from the record without any interference by the weight of the stylus plate; in fact, the greater weight and inertia of the stylus plate rendering the operation more perfect. I also have devised a special means for minimizing or entirely obviating any tendency of the stylus point to vertical movement; that is, any tendency to movement along the record and parallel with its axis.

In the foregoing described mechanism it' will be seen that the attachment of the spring 41 at a point at some distance from the point of support 35 will cause a certain tendency' of the stylus plate .to come back to the position shown in Fig. 2 if either end is raised or depressed. Thus, should the stylus point be lowered by anv vertical movement of the record groove, there is immediately called into play a force tend ing to move the stylus point back to its horizontal position opposite the point of support 35. This vertical movement may be caused by variation in the sound groove on the record, or, is more frequently the case where the record is supported vertirally, it is caused by the gradual settlingv of the record on its cone shaped mandrel.-

l` here may then be some tendency for the stylus point to jump from one groove into another and thus cause repetition or skipping in the reproduction. To obviate these possible difliculties I have shown a method whereby the spring 41 may be attached to the stylus plate at 'a point above or below the point of support 35 and as close theretoas is-desired. By appropriately placing' the point of attachment of the spring 41 the tendency to move the stylus point to its normal position may be lessened or increased. This mechanism is shown in Figs. 13 to 17. Here I have shown the aperture 35a in the stylus plate bridged by. two webs 100 having pivot depressions 101 therein.l In the present case I have shown these pivot depressions as'being exactly opposite the polnt of support where pointed pin 36'L rests in depression 37a in member 38a. Member 38a is bent so as to enter into the space between the two webs 100; but this construction may be as desired. Engaging with pivot depressions 101 is a pair of pivot points 102 and 1'03 mounted ,on a yoke 104. Pivot point 103 is adjustable so that the bearings may be kept in best working order. The spring 41 is attached to the lower end of yoke 104 so that both torsion and tension may be transmitted therethrough. Where the spring is thus attached to the stylus plate it will be seen that the downward tension of the spring will have absolutely no tendency whatever to move the stylus plate in a vertical plane about its point of support, the only tendency of the downward pull being to hold the pin 36a in its depression 37. If the pivot points 102 and 103 are placed slightly below the point of support, then there will be only a slight tendency to bring the stylus point back to itsA normal position. The pivot points may be placed above the point of support if desired; and this placementmay be used to counteract the tendency of the connecting wire 19'* which always tends to bring the stylus plate back to its normal posit-ion', coacting with spring 41 acting in torsion. The lengthening of this connection 19a, as shown in F ig. 13, tends to lessen the tendency for this action to bring the stylus p plate back to its normal position as regards vert-ical movement. With this mechanism it will be seen thatV the relative` positions of the point of support vof the stylus plate and the point of attachment of spring41amay be varied to suitanykparticular condition; and en account/of this variability lI do not. wish to limit myself` to any specific point of connection ofthe spring to the stylus plate. In Fig. 17 I have shown a modified means of securing the lower end of spring 41, consisting of a small rod 120 to whichy the lower end of the spring is attached for `both torsion and tension, this rod being' clamped in the split end of bar 43 by means of a small thumb screw 121. A small thumb nut 122 on the lower end of the rod 120 provides means for turning the rod and for moving it longitudinally as desired.

Havmg described my invention, I claimt 1. In an acoustic mechanism, a stationary frame, a vibrating member t-hereon, a stylus plate, a stylus thereon and connected to the vibrating member, a supporting member on the frame, a supporting member on the stylus plate and engaging the first named supporting member at a single point, said point of engagement being approximately coincident with the center of gravity of the stylus plate, and a torsion and tension member acting downwardly and rotatively on the stylus plate along andabout a vertical 'line passing through said point of engagement.

2. In an acoustic mechanism, a` stationary frame, a vibrating member thereon, a stylus plate, a stylus thereon and connected to the vibrating member, a supporting member on the frame, a supporting member on the stylus plate and engaging the irst named supporting member at a single point, said polntvof engagement being approximately in a vertical line through the center of gravity of the stylus plate, land a torsion and tension member acting downwardly and rotatively on the stylus plate along and about the said line determined by the center of gravity.

3. In an acoustic mechanism, a stylus plate mounting comprising a stationary member, and a supporting member on the stylus plate and engaging the stationary member at a single point, said point of engagement being approximately on a vertical line determined bythe center of gravity of the stylus plate.

a. Inan acoustic mechanism, a stylus plate 'mounting comprising a stationary member,

a support-ing member on the stylus plate and engaging the stationary member at a single point', said point of engagement being approximately on a vertical line determined bythe center of gravity of the stylus plate, and a torsion and tension member actinov on the stylus plate about and along the sai line determined by the centerof gravity.

5. In an acoustic mechanism, a stylus plate mount-ing comprising a stationary member, a supporting member on the stylus plate f and engaging the stationary member at a single point, said point of engagement being approximately on a vertical line determined by the center of gravity of the stylus plate, and a torsion and tension spring attached to the stylus plate and extending downwardly dlrectly beneath the said point of engagement and being stationarily fixed on its lower end.

6. An acoustic mechanism, comprising a Astationary sound box, a vibrating member therein, a stylus plate, a mounting for the stylus plate on the sound box and compris- `stylus plate on the sound box and comprising coperating members on the box and plate, the plate member resting on the box -member at a single point of engagement,

torsion and tension means acting on the plate about and downwardl along the vertical line passing through tie said point of engagement, a stylus having a vertical axis, the stylus plate having depressions adapted to receive the stylus axis, spring means for holding the stylus axis in said depressions, and a connection between the st lus and the yvibrating member in the sound ox.

\ 8. In an acoustic mechanism, a stylus plate Amounting comprising a stationary member,

a supporting member on the stylus plate and engaging the stationary member at a single point, said point of engagement being approximately at the center of gravity vof the stylus plate, and a torsion and tension spring attached to the stylus plate approximately at the center of gravity of the stylus plate.

y 9. In an acoustic mechanism, a stylus plate mounting comprising a stationary member, a supporting member on the stylus plate and engaging the stationary member at a single point, Asaid point of engagement being approximately at the center of gravity of the stylus plate, a yoke pivotally attached to the stylus plate horizontally opposite the center of gravity thereof, and a. tension and torsion spring attached to the lower part of the yoke.

' l0. In an acoustic mechanism, a stylus plate mounting comprising a stationary member having a pivot depression therein, a pin on the stylus plate having a pointed end resting in said depression, the point of support thus formed approximately coinciding with the center of gravity of the stylus plate, a yoke pivotedl to the stylus plate on a horizontal axis passing approximately through said center of gravity, the yoke depending below the stylus late, and a torsion and tension spring attaciied to the lower portion of the yoke and acting in torsien and tension about and along a vertical pin on the stylus plate having a pointed end resting in .said depression, the point of support thus formed approximately coinciding with the center of gravity of the stylus plate, a yoke pivoted to the stylus plate on a hori zontal axis passing approximately through said center of gravity, the yoke depending below the stylus plate, and a torsion and tension spring attached to the lower portion of the yoke and acting in torsion and tension about and along a vertical line passing through the point of support of the stylus plate.

12. In an acoustic mechanism, a stationary frame, a stylus carrying member, .cooperating supporting members on said member and the frame and having but a single point of contact, and a torsion spring attached to the said member and acting about a vertical axis determined by said point of contact.

13. lin an acoustic mechanism, a stationary frame, a stylus carrying member, co-

operating supporting members on the said member and frame and having but a single point of contact approximately in a vertical line through the center of gravity of saidl member, and a torsion and tension spring acting downwardly and rotatively on said member approximately along and about the said line determined by the center of gravity.

14. In an acoustic mechanism, a stationary member, a stylus plate, cooperating support members on the stationary member and plate engaging each other at but a single point ot' contact, and yielding means acting along the vertical axis determined by said point of support to move the stylus plate horizontally about the said point of support. in Witness that l claim the foregoing I have hereunto subscribed my name this 13th day or' November 1911.

HARRY T. SCOTT. Witnesses:

JAMES T. BARKELEW, JAS. H. BALLAGH. 

